School-slate



(No Model.)

F. A. OUVRARD.

SCHOOL SLATE.

` By @a/ew Mm.,

ANDREW BLRAHAM,PHUTO-UTMQWASMINGTOMUC.

r UNITEDv STATES PATENT OFFICE.

FRANK A. OUVRARD, OF DETROIT, MICHIGAN.

SCHOOL-SLATE.

SPECIFICATION forming part of Letters Patent No. 552,584, dated January '7, 1896. Application led March 9, 1894. Serial No. 503,003. (No model.)

To @ZZ whom, it may concern:

Be it known that I, FRANK A. OUVEARD, a citizen of the United States, residing at Detroit, county of Wayne, State of Michigan, have invented a certain new and useful Improvement in School-Slates; and I declare the following to be a full, clear, and exact description of the inven tion,such as will enable others skilled in the art to which it pertains to make and use the same, reference being had to the accompanying` drawings, which forni a part of this specification.

My invention relates to so-called schoolslates,77 although it may be used for such or analogous purposes; and it consists in certain improvements therein, hereinafter described and claimed.

In the drawings, the figures represent opposite sides of the same slate, with edges cut away in a sectional form in order to fully show the manner of construction, Figure l representing a black surface and Fig. 2 representing a White surface, and each being the obverse of the other.

In the drawings, A A represent the slateframes, which are constructed in the usual form and have therein rabbets or grooves B B, intended to claspand hold firmly the sheet of material upon which inscriptions may be made. Instead of employing the ordinary slate, however, I employ two plates of glass or equivalent transparent material C D. The outer surfaces of these are roughened sufciently to permit the writing upon them easily by either slate or lead pencil, as maybe de-A sired. These two sheets of glass are placed back to back, withV their roughened surfaces outward, the inner face C being preferably colored with black paint or analogous coverwhite paint or analogous covering. The painted surfaces are thus contiguous, and may be in contact, and both are protected by the transparent plate upon which writing or inscriptions, as shown in Fig. l, may be made, using preferably a slate-pencil upon the dark side and a lead-pencil on the light side. These slates are much stronger than the ordinary slate, besides being adapted to a greater variety of uses. Their surfaces are much harder and are not liable to be scratched or otherwise injured short of absolute fracture.

It is obvious that the frame A A holds the ing and the inner face 'D being colored with t two plates of glass together in the position indicated.

In the drawings, Erepresents the sectioned edge of the dark paint and F the sectioned edge of the white paint I do not desire to confine myself to glass as the transparent medium, as Celluloid, mica, or other transparent materials might be used in their stead, I, however, prefer glass on account of its relative hardness.

Glass slates or writing-tablets have been ,provided with a separable opaque backing,

and such backing has been placed between two glass plates. It is characteristic of my improvement that the use of a separate backing, which necessarily has an objectionable reiiecting-surface of its own, is avoided by applying adherent coloring-matter directly to the surfaces of transparent plates, and, further, that the plates are held together so that the colored coats are contiguous and each protected from wear and scratching, and that said colors are contrasting, and that incidentally there are provided in one frame and in one slate two surfaces adapted for various uses, as above specified.

Glass has been painted and framed to produce so-called blackboards and the side opposite the painted surface adapted for use with a pencil, the object being to avoid the use of the pencil directly on the painted surface, and such matter is not of the present invention, and the protection hereinabove referred to results from inclosing the painted surfaces, so that they are defended from scratches and wear, this being a matter of importance in portable slates, such as are designed for the use of individual scholars.

A composite slate consisting of two plates of transparent material provided on their inner sides with coloring matter and a frame holding the plates with their colored surfaces in contact with each other whereby the said coloring matter on both slates is protected and the plates supported and strengthened one by the other, substantially as described.

In testimony whereof I sign this specification in the presence of two witnesses.

FRANK A. OUVRARD. Witnesses:

FRANCES CLOUGH, R. A. PARKER.

IOO 

